1. Field of the Invention
The present invention relates to a roll baler including circumferentially rotatable conveyor elements limiting a compression space therebetween, and a device for wrapping up a roll bale, which is formed in the compression space, with a section of a sheath web, the wrapping-up device including pivotable start-up means for pressing the sheath web, at least in an initial phase of a wrapping-up process, against a surface of one of the rotatable conveyor elements and separation means for cutting the sheath web off after the wrapping-up process ends and pivotable between cutting and non-cutting positions.
2. Description of the Prior Art
A roll baler of the type described above is disclosed in German Utility Model DE 296 12 863 UI. In the roll baler of this utility model, a sheath web is pressed by a pressure element against a side of a conveyor band remote from the compression space. The sheath web is delivered into the pressure space through an admission gap by a 180xc2x0 deflection element. The drawback of such deflection of the sheath web, in particular with a conveyor bank having a specific texture, consists in that the sheath web is not always entrained by the belt. The separation device is supported on a second axle offset with respect to the pivot axle of the pressure element, and is connected mechanically with the pressure element. For cutting off the sheath web, the separation device should be pivoted over a relatively large arc over the pressure element and into a V-shaped guide of the pressure element. With such an arrangement many parts become necessary, on the one hand, and, on the other hand, the separation device requires a relatively large space for its installation and operation. However, the main drawback of the known device consists in an unreliable cut-off of the sheath web due to the fact that the sheath web and the separation device move both in the same direction. As a result, no definite edge of a cut can be produced. This results in that a poorly cut sheath web is partially taken up the separation device and/or is only partially removed from the conveyor band. In addition, a poor cut makes the introduction of the sheath web into the compression space more difficult.
Accordingly, an object of the present invention is to eliminate the above-discussed drawbacks of the wrapping-up means of the prior art roll baler.
This and other objects of the present invention, which will become apparent hereinafter, are achieved by mounting both the pressure element and the separation device on the same axle. In this way, the functions of starting the delivery of the sheath web and separation of the sheath web by pivoting the start-up device in one direction and the separation device in another, opposite direction are realized unexpectedly easily. This, in case an automatic control is used, permits to effect both functions with a single drive. In addition, the cutting direction of the separation device can be so selected that it would insure a good cut. Both the start-up device and the separation device have a simple construction, small dimensions, are reliable, substantially wear-free, require little maintenance, and are economical in manufacturing.
A common adjustment of both the start-up device and the separation device permits to provide a particularly simply, reliable and economical construction.
According to a preferred embodiment of the present invention, both the start-up device and the separation device are arranged in a common, pivotally supported frame. This permits to obtain a compact, rigid unit.
A particular reliable arrangement is obtained when the distance between the separation device and the pivot axle is smaller than a distance between the pivot axle and the start-up device, and the pivoting or drive means is connected with at least one of the pivot arms in which the pivot axle is supported. This arrangement, on one hand, provides for a sufficiently large distance between the band and the start-up device which permits the sheath web to be freely suspended in the intermediate space, preventing inadvertent entraining of the sheath web. On the other hand, the pivotal movement of the separation device is relatively small, with the prestressed sheath web having already passed past the separation device relatively far into the compression space. Furthermore, a direct drive is insured by connecting the drive means with one of the pivot axle-supporting arms.
In a further preferred embodiment of the present invention, the start-up device has a freely rotatable pressure roll. The pressure roll presses the sheath web against the conveyor band at least at the start of wrapping-up process and is rotated by the web. Then, the pressure roll pivots into the intermediate neutral position, and the formed roll bale pulls the sheath band directly from the supply roll.
The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiments, when read with reference to the accompanying drawings.